More release branch exclusions (#5919)

* More release branch exclusions

* wording

.github/workflows/build-pull-request.yml

@@ -65,11 +65,15 @@ jobs:
 
   # this is not a required check to avoid blocking pull requests if external links break
   markdown-link-check:
+    # release branches are excluded to avoid unnecessary maintenance
+    if: ${{ !startsWith(github.ref_name, 'release/') }}
     uses: ./.github/workflows/reusable-markdown-link-check.yml
 
   # this is not a required check to avoid blocking pull requests if new misspellings are added
   # to the misspell dictionary
   misspell-check:
+    # release branches are excluded to avoid unnecessary maintenance
+    if: ${{ !startsWith(github.ref_name, 'release/') }}
     uses: ./.github/workflows/reusable-misspell-check.yml
 
   required-status-check: